JP2002506934A - Method and apparatus for deinking paper - Google Patents

Abstract

  (57) [Summary] A method of removing ink from a paper sheet by removing toner on the paper sheet, comprising a non-toxic water-soluble ink removal liquid (this ink removal liquid is used to wet the paper sheet and expand the fibers of the paper sheet). Water, a water-soluble surfactant for reducing the surface tension of water so that the sheet is easily wetted with water, and softening the toner without dissolving the toner, and forming a bond between the toner and the sheet. Dampening the paper sheet with 2 or less water-soluble solvents to break up) removing the softened toner from the sheet to form toner particles; heating the sheet to evaporate the ink drainage, and Removing the solution from the paper; calendering the paper sheet and returning the sheet to a predetermined size for immediate reuse.

Description

DETAILED DESCRIPTION OF THE INVENTION

Related Application This application is part of a continuation of US patent application Ser. No. 08 / 652,146, filed May 13, 1996, entitled “Methods and Apparatus for Deinking Paper”.

FIELD OF THE INVENTION The present invention relates to a method and apparatus for deinking paper, and more particularly to a non-impact (non-impact) method using a water-soluble, non-toxic, non-toxic de-inking solution. The present invention relates to a method and an apparatus for deinking paper containing ink.

BACKGROUND OF THE INVENTION In the United States, paper waste accounts for 31% of total municipal and industrial waste by weight, and well over half by volume. Waste from office laser printers, photocopiers and facsimile machines makes up a significant portion of the total amount of paper waste in the United States. In the United States, laser ink paper waste accounts for 24% by weight and about 40% by volume of total household and industrial waste.

[0004] Printing on paper is performed using one of two types of inks, namely, impact inks and non-impact inks. The impact ink is, for example, an ink used in letterpress printing and lithography. Impact inks consist of carbon black or dyes and are usually water-soluble. Non-impact or "laser" inks are, for example, inks used in laser printers, photocopiers and facsimile machines.

In impact printing, the ink does not fuse to the paper and is easily removed from the paper. Paper printed by the impact method has been successfully deinked for many years. However, non-impact inks, or toners, are difficult to remove as the ink particles fuse to the paper and to each other.

[0006] Recently, non-impact printed paper has been regenerated in large quantities using toxic chemicals in paper mill environments, and the chemicals have been recycled using the environment and the chemicals. It poses a threat to working or nearby people. The non-impact ink comprises carbon black, pigment, resin and iron oxide. Usually, the paper is loaded in bulk in a chemical tank to soften the toner. The paper is then repulped to remove the toner. Printing with such an ink is performed between 160 ° C and 204 ° C. Similarly, removal of these inks usually requires comparable temperature ranges. This method is expensive and cannot produce high quality recycled paper. In addition, the cost of recycling labor is considerable because the paper is transported to a remote recycling location for recycling.

Most research aimed at regenerating this paper has focused on the one hand on the development of new and better chemical formulations and on the other hand on the design of new and better repulping plants. . Recently, combined mechanical / chemical processing equipment has been developed and tested.
However, problems still exist regarding the separation of toner particles from paper sludge. As a result, many toxic and alkaline chemicals are used in large quantities, and the fiber recovery is only about 70%. Such chemicals include sodium hydroxide for fiber swelling, toner detachment and dispersion; sodium silicate for peptization, alkalinity and peroxide stabilization;
Sodium carbonate for alkalinity, buffering and water softening; sodium phosphate for alkalinity, deflocculation, toner dispersion and metal ion capture; solvent for solvation and softening; agglomeration, dispersion, wetting, emulsification Surfactants for solubilization and peptization;
Polymeric dispersants for dispersing, preventing reprecipitation and trapping metals; hydrogen peroxide, sodium hydrogen sulfate and chlorine for bleaching and bleaching. This is just a list of some of the commonly used chemicals, which are used in various combinations at various stages of regeneration and deinking. As discussed above, most of these chemicals are harmful, toxic and alkaline, and pose a serious threat to the health of those who come into contact with them and their vapors.

[0008] Small, unique regenerators have been developed that can remove toner and recycle paper printed thereon with non-impact inks. One such inventor is disclosed in U.S. Pat. No. 5,463,447 (inventor: Kurotori et al.), Which discloses a method for converting a sheet of paper printed on a photocopier. A method for removing toner is disclosed. However, the device does not modify the adhesion of the toner such that the developer used in the photocopier is weak enough that the toner image can later be removed from the paper on which it is formed. You need to be quality. Thus, the device of this patent does not properly deink the paper unless it is first printed with a special toner that has sufficiently low adhesion.

US Pat. No. 5,528,788 [Inventor: Yamamoto et al.] Discloses an ink removal device that uses an ink removal fluid containing a chemical from a list of cleaning companies. . Although the exact chemical composition is not specified, fluids of at least eight and as many as twenty-four components are disclosed.

Furthermore, although the exact formulation is not disclosed, it is clear that the disclosed materials are not water soluble because of the use of solvents. In addition, the list of chemicals presented by Yamamoto will not be able to prepare deinking fluids at pH 6.5-7.5.

[0011] Finally, Yamamoto teaches that surfactants are not required. Accordingly, Yamamoto has developed a surfactant, HL, which is fundamentally important for the wettability of its deinking fluid.
B is not considered.

Another apparatus disclosed in US Pat. No. 5,353,108 (Tsukamoto) is used to clean printed paper. However, this paper must be a paper that can be erased with an eraser or the like containing a base material and a release agent. The paper is fed between an adhesive roller and a platen. On the surface of the adhesive roller, there is a heat-soluble resin in a molten state, and the heat applied to the heat-soluble resin by a heat source converts the heat-soluble ink into a resin on the erasable paper. Wrap in and peel off from the surface of the paper. These devices have limited scope,
And in general, it would not be possible to use it on any piece of paper containing non-impact ink. That is, these apparatuses can be used only with a specific type of paper, for example, a paper that can be erased with an eraser or the like, or a paper using a specific toner having low adhesive strength.

[0013] Apart from the need and benefit of reclaiming paper, protecting and protecting privacy and disclosure and dissemination outside of a company or agency, or even to a limited number of individuals within such an organization. There is a need for protection of information that does not want to be done. Business methods and practices are often a secret of commerce, and are undesirable to be seen by anyone other than the people employed by the company, and often by a small number of people. The same is true for government agencies, specialized agencies and similar agencies that have a duty of confidentiality for security for customer protection and national security. Such requests made for documents containing sensitive, personal or confidential information are strictly prescribed. Obviously, such documents are not sent out for playback. Further, shredding such documents can be outwitted by restoring the shreds. Accordingly, there is a need for a method and apparatus for deinking paper that allows such documents to be reproduced without jeopardizing the security of the information contained therein.

The standard cost of shredding and regeneration is as high as two cents per sheet, and the regeneration yield can be very low. Similarly, the conventional regeneration method is 1 cent per sheet with a 70% regeneration yield. This does not take into account the transportation costs of the paper to be recycled.

SUMMARY OF THE INVENTION It is, therefore, one object of the present invention to provide a method and apparatus for deinking paper containing ink printed on any type of paper in a non-impact printing process. It is.

It is a further object of the present invention to provide a method and apparatus for inking paper that is accomplished in a small, self-contained, closed device. It is a further object of the present invention to provide a method and apparatus for inking paper that can be used in an office environment and is non-toxic and harmless to users and the environment.

It is a further object of the present invention to provide a method and apparatus for deinking paper, which improves the quality of the recycled paper and further allows the recycled paper to be reused directly. It is.

It is a further object of the present invention to provide a method and apparatus for deinking paper that is less expensive than conventional methods. It is a further object of the present invention to provide a method and apparatus for deinking paper independent of paper deterioration.

It is a further object of the present invention to provide a method and apparatus for deinking paper that is very cost-effective compared to purchasing new paper. It is a further object of the present invention to provide a method and apparatus for deinking paper without having to dissolve the toner to be removed.

A further object of the present invention is to collect the removed toner for regeneration,
It is to provide a method and apparatus for deinking. It is a further object of the present invention to provide a method for ink removal, in which the evaporated ink removal solution is condensed and collected for regeneration.

A further object of the present invention is to provide a method and apparatus for ink removal that improves security by preventing the detection of information previously printed on the recycled paper. That is.

The present invention provides a truly effective, safe and cost-effective system for paper de-inking that moistens water, water-soluble surfactants and the paper, thereby completely swelling the fibers of the paper. And the use of two or less water-soluble solvents that soften the toner thereon and break the bond between the toner and paper without dissolving the toner. The use of the system facilitates the removal, collection and recovery of toner, and also the collection, condensation and recovery of the ink removal solution without exposing the user to toxic chemicals and fumes, Improved quality paper can be produced for direct reuse, and information previously printed thereon can be prevented from being detected.

The method of the present invention comprises water for wetting a sheet of paper and swelling the fibers of the sheet, and water-soluble surfactant for reducing the surface tension of water to increase the wettability of the sheet with water. Non-toxic water-soluble ink drainer, comprising no more than two water-soluble solvents for softening the toner without dissolving the toner and breaking the bond between the toner and the sheet It is characterized in that the paper sheet is deinked by wetting the paper sheet with the solution and thereby removing the toner on the paper. The softened toner is removed from the sheet and regenerated into toner particles, the sheet is heated to evaporate the deinking solution, the deinking solution is removed from the sheet, and the paper sheet Are calendared for direct reuse.

In one preferred embodiment, the ratio of water to surfactant in the ink removal solution is:
10: 1. The surfactants include Triton X-155 and Triton X-155.
305, Triton X-405 and BRD2311. The deinking solution contains a solvent and the ratio of solvent: water + surfactant may be 3:10. The solvent is a C12-C14 aliphatic hydrocarbon. This solvent is an ether. This solvent is diethylene glycol n-butyl ether. The toner particles are collected and recycled. Steam generated by heating is collected. This collection of vapors includes condensation, the collected vapors being returned to the liquid de-inking solution and recirculating the condensed de-inking solution. Removal includes wiping the sheet to remove toner particles. The wiping operation includes a rotating coiled brush to remove toner particles from the sheet. The wiping operation includes a step of collecting toner particles from the coiled brush. The collecting step includes combing the coiled brush to remove toner particles from the brush. The combing step involves depositing the toner particles in a collection compartment. The heating step includes blowing heated air on the sheet to dry it. The temperature of the heated air is in the range of 60C to 70C. The calendering step includes supplying a sheet between heated rollers. The temperature of this roller ranges from 20 ° C to 60 ° C. The water makes up from 75% to 87% of the ink removal solution. This surfactant is used in an amount of 1% to 3% of the ink removing solution.
Make up%. This solvent makes up 15% to 20% of the ink removal solution. The pH of the ink removing solution is 6.5 to 7.5. The solvent comprises a glycol ether and an aromatic hydrocarbon. The glycol ether is selected from the group consisting of ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, ethylene glycol n-butyl acetate and diethylene glycol n-butyl acetate. The aromatic hydrocarbon is selected from the group of ethyl 4-methoxybenzoate, ethyl 3-methoxybenzoate and ethyl 2-methoxybenzoate.

The present invention also provides water for wetting a sheet of paper and swelling the fibers of the sheet, and a water-soluble surfactant for reducing the surface tension of water to increase the wettability of the sheet with water. And a non-toxic water-soluble deinking solution comprising two or less water-soluble solvents for softening the toner without dissolving the toner and breaking the bond between the toner and the sheet. An apparatus (system) for removing ink from a paper sheet by removing toner on the paper, including a method of wetting the paper sheet. A device for regenerating toner particles by removing the softened toner from the sheet, a heating device for evaporating the ink removing solution,
There are devices that remove the solution from the sheet, and devices that calender the sheet for direct reuse of the paper sheet.

In one preferred embodiment, the ratio of water to surfactant in the deinking solution is 10: 1. The surfactants are Triton X-155, Triton X
-305, Triton X-405 and BRD2311. The deinking solution contains a solvent and the ratio of solvent: water + surfactant may be 3:10. The solvent is a C12-C14 aliphatic hydrocarbon. This solvent is an ether. This solvent is diethylene glycol n-butyl ether. An apparatus for collecting the toner particles is included. An apparatus for recirculating the toner particles is included. A device for collecting steam generated by heating is included. The device for collecting the vapor includes a device for condensing the collected vapor and returning it to a liquid ink removing solution, and a device for recirculating the condensed ink removing solution. The removal device includes a device that wipes the sheet to remove toner particles. The wiper includes a rotary coiled brush for removing toner particles from the sheet. The wiper includes a device that collects toner particles from the coiled brush. The device for collecting toner particles includes a device for combing a coiled brush for removing toner particles from the brush.
The combing device includes a device for depositing the toner particles in the collection compartment.
The heating device includes a device that blows heated air to the sheet to dry the sheet. The temperature of the heated air is in the range of 60C to 70C. The calendering device includes a heated roller. The temperature of this roller is 20 ° C
To 60 ° C. Water comprises 75% to 87% of the ink removal solution. This surfactant constitutes 1% to 3% of the ink removal solution. The solvent makes up 15% to 20% of the deinking solution. PH of this ink removal solution
Is 6.5 to 7.5. The solvent comprises a glycol ether and an aromatic hydrocarbon. The glycol ether is selected from the group consisting of ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, ethylene glycol n-butyl acetate and diethylene glycol n-butyl acetate. The aromatic hydrocarbon is selected from the group of ethyl 4-methoxybenzoate, ethyl 3-methoxybenzoate and ethyl 2-methoxybenzoate.

Disclosure of Preferred Embodiments Other objects, features and advantages will become apparent to those skilled in the art from the following description of preferred embodiments and the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a paper recycling system 10 for deinked paper. This system is primarily designed for de-inking paper containing non-impact ink, but is equally suitable for de-inking paper containing impact ink. Non-impact inks are toners applied to paper by, for example, laser printers, photocopiers and facsimile machines. System 10 is a compact, self-contained, sealed unit. This unit has a length of 38 inches, a width of 23.5 inches, and a height of 38 inches. This system
It requires no external connection other than a power cord, and is very suitable for office environments.
It is safe. The system 10 includes a used paper tray 12, a cleaned paper tray 14, and a rejected paper tray 16 for receiving rejected paper that cannot be recycled by the system 10. An electronic sensor (not shown) scans each sheet to detect if toner is still remaining on the paper. If so, the paper is sent to a rejected paper tray 16. The system 10 operates under the control of a control unit 18. The control unit 18 includes typical indicator lights (e.g., power on, prepare, check paper, add ink drain, clean rollers,
Etc.), switches on and off, switches to start and stop the cleaning process, and the sheet has passed through the system 10 since the sheet has been completely cleaned or decopied or further cleaned A responsive slide used to indicate what to do.

A location for wetting, wiping, and drying (a location for achieving ink removal according to the present invention, shown in FIG. 2) is included in compartment 20. Doors 23 and 24
May be used for chemical preservation. System 10
May be mounted on wheels 25, in which only two of the wheels are shown.

Compartment 20, shown in detail in FIG. 2, receives paper from used paper tray 12 (not shown) at entrance 30. The heating plate 29 heats the paper to a temperature between 25C and 60C to soften the toner before entering the compartment 20. Paper is nip roller 3
1 and 32 to the compartment 20. The nip roller applies an individual used paper sheet (for example, the sheet 33) to the ink removing liquid application unit 34 under the control of the control unit 19 in FIG. In the immediate vicinity of the ink drainage application section 34, the sheet 33 meets the drive transport belt 36. The belt conveys used paper sheets through compartment 20 until the used paper sheets are stored in the cleaned paper tray 14. The drive conveyance belt 36 is driven by a main roller driving device 38. The drive 38 includes a motor 40 that drives the main roller 42 in a clockwise direction. The belt 36 is guided by idler rollers 44 to 50 and driven counterclockwise by the main roller 42. Idler rollers 46-50 include spring tension adjusters 46a-50a. These adjusters adjust the tension of the drive conveyance belt 36.

The part 34 includes a first roller 52. This first roller is also driven by the main roller drive 38 and rotates clockwise. Intermediate roller 54
The roller 52 in combination with rotates the ink draining roller 56. The roller 56 is immersed in a trough 58. This tank stores a predetermined amount of ink drainage supplied from the reservoir 60. The reservoir 60 is preferably a removable cartridge, such as a toner cartridge in a photocopier. The reservoir 60 slowly supplies the ink drainage to the tank 58. Roller 56
Is rotated, the ink bleeding liquid is discharged from the tank 58 by the roller 56 to the intermediate roller 5.
Transported to 4. This intermediate roller sequentially carries the liquid to the first roller 52.
As the paper sheets are conveyed along the drive transport belt, the liquid from the first rollers 52 is applied to each sheet.

On the other hand, the ink draining liquid may be sprayed onto the sheet 33 by the spray nozzle 57. The spray nozzle 57 sprays the ink draining liquid uniformly in such an amount that the sheet 33 is sufficiently wetted. It has been found that the toner can be easily removed after 3-4 seconds at 60C. This time necessarily increases with decreasing temperature.

[0033] The ink draining liquid consists of water and two water-soluble solvents. Including a surfactant,
Performance may be improved. It is known that the pH of the ink removing liquid is in the range of 6.5 to 7.5, particularly 6.8, and the density and the boiling point thereof are approximately 1 respectively.
. 0 and 100 ° C., similar to water. Therefore, the ink bleeding liquid is not harmful to the user and the environment. Moreover, since the components evaporate with the water, there is no need for rinsing.

The amount of water in the whole liquid should be between 75% and 87% by volume. When a liquid comes into contact with a solid, the molecules adhere to the solid at the interface. The molecules spread on the solid and the surface area of the liquid increases. This phenomenon is called wetting. Good wetting facilitates rapid penetration of chemicals into the paper fiber network and fiber-toner contact areas. This wetting phenomenon aids in breaking and separating the toner from the fibers. If the percentage of water in the total volume of the liquor is significantly above 87%, the liquor is in a fairly aqueous state. This condition would make the paper too soft and would break the paper even under minimal mechanical pressure, for example, pressure from a coiled brush. If the percentage of water is significantly less than 75%, the paper fibers will be hardened due to physical bond formation. Hydrocarbon solvents are known to harden cellulosic materials because they form strong physical bonds with certain cellulosic materials. However, because the paper is not completely wet, the toner is not completely softened. In this case, it is more difficult to remove the toner with the help of a brush.

The volume of the two solvents is usually not more than 20% and not less than 10%. Solvents that can dissolve most printing inks can be used. However, such solvents are expensive and cannot be used cost-effectively for recycling. Another disadvantage is compatibility with water. To be effective, the solvent needs to be incompatible with water at low concentrations (<1000 ppm). Unfortunately, most such solvents are compatible with water. In addition, due to environmental concerns, EPA regulations do not allow the use of some good solvents, especially halogenated hydrocarbons. As a result, most of the commonly used solvents are aliphatic hydrocarbons. Surprisingly, it has been found that formulations composed of water and two water-compatible solvents are capable of softening and even dissolving the toner depending on their proportion and temperature. . However, in a preferred embodiment, the toner only softens but does not dissolve. This allows
Prevents fading of decopied paper and recycling of solution.

The two solvents are a glycol ether or glycol ester and an aromatic hydrocarbon. Examples of glycol ethers and glycol esters include ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, ethylene glycol n-butyl acetate, and diethylene glycol n-butyl acetate. The aromatic solvent can be selected from aromatic esters and alkylphenols, such as ethyl 4-methoxybenzoate, ethyl 3-methoxybenzoate, and ethyl 2-methoxybenzoate.

In addition to the solvents mentioned above, the solvent may be a C12-C14 saturated aliphatic hydrocarbon or ether. Preferably, the solvent is solvent 900, especially diethylene glycol n-butyl ether. In another chemical, water and a surfactant are used in three:
The same solvent may be mixed with the mixture mixed at a ratio of 10.

[0038] The ratio of aliphatic solvent to aromatic solvent can typically be between 4: 1 and 5: 1, depending on whether a surfactant is included. The hydrophilic-lipophilic balance (HLB) of a given surfactant can be changed by changing the temperature of the drug, adding a solvent, or both. The type and amount of solvent used is important to obtain or maintain the desired HLB. In the present invention, the ratio of such solvents is important to maintain and obtain HLB 7-9. If the combined proportion of the two solvents is significantly greater than 20%, melting and brush-assisted toner release tend to be more difficult. On the other hand, if the amount of the solvent is too large, the adhesion of the toner to the sheet and the smear will be prevented.

In a preferred embodiment, the total amount of surfactant in the deinking solution may be less than 5%, preferably in the range of 1-3%. The surfactant in this situation typically does not need to exceed 5% because it lowers the surface tension of water and mainly improves wetting. Too little surfactant will result in poor wetting of the paper, and too much will cause soiling of the toner.

A surfactant is a substance that activates a surface. In deinking, surfactants serve to lower the surface tension of the water and make it more effective wetting. The solvent is more effective because water also contains the solvent. The surfactant thus adsorbs to the surface and aids in ink removal, solubilization, dispersion and emulsification. Thus, surfactants mainly increase the speed of ink removal. It is most useful to carefully select and balance the surfactant in any deinking chemical. The surfactant has an affinity for oil (hydrophobic) and an affinity for water (hydrophilic)
It consists of another part. There are two types of surfactants, non-ionic and ionic. In nonionic surfactants, the hydrophilic moiety is usually a highly polar substituent, while in ionic surfactants it is an ionic group. In both types of surfactants, the hydrophobic moiety is a long chain hydrocarbon residue. Surfactant chemistry is complex and not well understood.

Even if one surfactant is effective for a particular toner and a particular grade of paper, it is not necessarily the same for the other. The type of solvent used with the surfactant can modify the HLB of the surfactant, thereby affecting the ability to lower the surface tension of water. With HLB 4-6, the surfactant acts as a water-in-oil emulsifier. Similarly, when HLB 8-13 is used, the surfactant acts as an oil-in-water emulsifier. In 13-15 the surfactant acts as a detergent and in 15-18 it acts as a solubilizer. Thus, the HLB of the deinking solvent of the present invention is 7-9, at which time the surfactant will act as a wetting agent. Commonly used surfactants are ethoxylated alkylphenols,
Ethoxylated linear alcohols and fatty acid soaps. However, rinsing is not required because most of the surfactant is removed along with the toner because of its low percentage.

The surfactant is, for example, Triton X-155, Triton X-305, Triton X-305
Although it may be 405, a preferred surfactant is BRD-2311. Take
The chemical composition of the surfactant is as follows:Triton X-155 Chemical composition: methylenebisdiamyl-phenoxypolyethoxyethanol / 679
06-06-3; isopropanol / 67-63; water / 7732-18-5;
Polyethylene glycol / 25322-68-3 Manufacturer: Union CarbideTriton X-305 Chemical composition: poly (oxy-1,1,3,3-tetramethylbutyl) phenyl-W-
Hydroxy- / 9036-19-5; poly (oxy-1,2-ethanediyl, A
-Hydro-W-hydroxy- / 25322-68-3; water / 7732-18-5
Manufacturer: Union CarbideTriton X-405 Chemical composition: octoxyphenoxypolyethoxyethanol / 9036-19-5
Water / 7732-18-5; polyethylene glycol / 25322-68-3 Manufacturer: Union CarbideBRD-2311 Chemical composition: This surfactant is trade secret; however, ethoxylated linear alcohol
Or ethoxylated alkylphenols, or both, with small amounts of Na ⁺ It is thought to include. Manufacturer: Buckman Laboratories A further chemical that can be used consists of a 10: 1 ratio of water to surfactant.
One obtained by adding an enzyme at a ratio of 1:33 with respect to the basic drug is mentioned. Enzyme is BU
ZYME2522 is preferred. The enzyme is manufactured by Buckman Laboratories and
These are also trade secrets. This chemical uses BRD-2311 as a surfactant
Works best when

After each sheet of paper leaves station 34, it proceeds to wiping station 64 without interruption. Alternatively, each sheet may be transported to station 62 where the movement of the driven carrier belt 36 is stopped for approximately 10-15 seconds, and depending on the temperature of the system, the non-impact ink (
Toner) with an ink removal solution. Further heating by the heater 63 makes it possible to easily soften the toner without stopping the operation belt.

After the non-impact ink has softened, the paper is moved to a wiping station 64 that includes primary rollers 66 and is driven by main roller drive 38. The primary roller includes a coiled brush that includes bristles 67 on its surface, which gently wipes the surface of the paper as it passes through the wiping station 64 to remove toner particles. The bristles are typically made from a low density polyethylene material. Comb roller 68 can be used to continuously remove toner ink particles from the bristles of roller 66. The wiping section 64 includes a collection section 65. The removed particles are collected by a collection station 65 that includes a collection compartment 69, which can be a removable cartridge similar to a standard photocopier cartridge. A gentle wipe removes most of the toner without disturbing the paper fibers. The rollers 66 are arranged and formed to rotate in the direction of movement of the paper sheet in the system 10,
Roller 66 may be rotated in the opposite direction. Also. Roller 66 may be oriented at an angle to sheet 33a, as shown in FIG. 3, to direct toner particles to collection compartment 69a, assuming the coiled nature of roller 66. In FIG. 2, the toner is removed from the surface of the scraper primary roller 66.

A second wiping station 72 may be arranged similarly to the wiping station 64, which includes a primary roller 74, bristles 75 comb rollers 76, a scraper 78 and a collection section 79. This section operates to provide additional wiping action to remove any residual traces of toner.

The dryer section 92 includes a blower device 94 and a duct 96 for ducting the heated air flow generated by the blower 94 to dry the paper sheet as it passes through the dryer section 92. To the surface of the paper sheet. The air striking the sheet is typically heated to a temperature in the range between 60 ° and 70 ° C. Since the deinking solution is water soluble with a pH of 6.5-7.5, typically a pH of 6.8, and a boiling point of 100 ° C., the solution components evaporate without any residue. Thus, no rinsing of the sheets is necessary.

The fluid collection section 88 includes a fan 80 that draws the vaporized ink drainage solution through a duct 82. The condensing means 84 includes a condensing coil that condenses the vapor back into a liquid; the liquid is collected in a liquid recovery section 86. The liquid collection compartment 86 includes a replaceable cartridge that can be removed when full and can be replaced by another empty collection compartment. This not only allows the ink removal solution to be recycled, but also prevents vapor (although non-toxic to the user) from the fluid from escaping into the atmosphere and generating an unpleasant odor. . When the recovery compartment 86 is full, it can be removed and returned to either the wet department 34, the return reservoir 60, or disposed of after a predetermined number of uses until disposal or other use. Can be done.

Alternatively, the condensed liquid may be fed back directly to the reservoir 60. Since the de-inking solution of the present invention does not dissolve the toner, the condensed de-inking solution is not contaminated and can therefore be reused, thus saving the operating costs of the decopier. Therefore, the condensation coil 84 disposed in the collection duct 86a
a allows for the immediate reuse of the recycled fluid.

Thus, the deinking system of the present invention not only provides a non-toxic and non-caustic deinking solution, but also that solution and toner particles are recycled,
It is environmentally friendly because it is not simply discarded.

After the sheet 33 exits the dryer section 92, it is driven by the main roller drive 38 and applied to a compression roller 98, which may be heated to a temperature in the range of 90-100 ° C. This further dries the sheet, removes any wrinkles that may be present from the paper, and returns the sheet to its original dimensions before stacking the sheet in the cleaned paper tray 14. At this time, the seat can be reused immediately. Furthermore, the quality of the sheet is in fact improved as a result of the deinking solution.
The solvent reinforces the paper fibers and improves the paper quality because of the strong physical bonds formed by the hydrocarbons and the paper fibrous materials. This further extends the life of the paper and allows up to five deprinting operations per sheet.

The criteria for security require that the information previously contained in the sheet cannot be detected. Infrared tests performed by the U.S. Army Criminal Investigation Laboratory of Forest Park, Georgia on sheets deprinted according to the present invention revealed no residual toner on the sheets. This test was performed on deprinted sheets using IR (infrared); ultraviolet (UV)-short and long wavelength;
light) and exposure to argon laser light.

The flowchart 100 of FIG. 4 illustrates the method of ink removal according to the present invention.
In step 102, the deinking solution formulated as described above is applied to the used paper to be deinked. The paper is then gently wiped in step 104 to remove the softened toner from the paper without disturbing the paper fibers. The toner particles are removed from the brush and collected for recycling. In step 106, the deinking solution is removed by heating the paper to a temperature between 60 ° and 70 ° C.

[0053] The deinked paper is dried in step 108 and the vaporized deinking solution is collected and condensed for recycling. The dried paper is compressed in step 110 to further dry the paper and to remove any wrinkles that may be present during preparation and ready for immediate reuse in step 112.

The systems and methods of the present invention provide a relatively small and effectively improved quality of any type of paper of any age including non-impact inks printed with any non-impact ink printing method. Create recycled paper costs. Furthermore, the inked sheet does not retain any trace of information previously printed on it, and is safe for both the user and the environment. The present invention produces 100% of the recycled material at a cost of 0.3 cents per sheet.

While certain features of the invention have been illustrated in some drawings and not shown in others, this is for convenience only and each feature may have any of the other features in accordance with the invention.
Alternatively, it can be combined with all.

[0056] Other embodiments will occur to those skilled in the art, and are within the scope of the claims.

[Brief description of the drawings]

FIG. 1 is a perspective view of a paper recycling system for deinked paper according to the present invention.

FIG. 2 is a schematic cross-sectional view of the system of FIG.

FIG. 3 is a top plan view of FIG. 2;

FIG. 4 is a flowchart illustrating an ink removing method according to the present invention.

[Procedure amendment]

[Submission date] April 2, 2001 (2001.4.2)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

FIG. 3

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Ash, James Tubot 01608, Mass., USA, Ward, Oreed Street 14, Number 103 F-term (reference) 3B201 AA04 AB14 BA02 BA14 BB21 BB92 BB94 BB95 CC12 4L055 AE05 AE10 AG34 AG99 AH29 AH50 CH30 EA20 EA30 EA32 FA21 FA30 GA35 GA50

Claims (53)

[Claims] 1. A method for deinking a sheet of paper by removing toner thereon, comprising dampening the sheet of paper with a non-toxic aqueous de-inking solution; Water to moisten the sheet of paper to swell the fibers of the sheet; water-soluble surfactant to reduce the surface tension of the water to promote wetting of the sheet with water; without dissolving the toner Containing no more than two water-soluble solvents to soften the toner and break the bond between the toner and the sheet, removing the softened toner from the sheet to form toner particles, heating the sheet Such a method comprising evaporating the deinking solution; removing the solution from the sheet; and rolling the sheet of paper back to its original size for immediate reuse. 2. A method for deinking paper according to claim 1, wherein the water and the surfactant are in a ratio of 10: 1 in the deinking solution. 3. The method of claim 2, wherein the deinking solution further comprises a solvent in a 3:10 ratio to water and surfactant. 4. The method for deinking paper according to claim 3, wherein the solvent is a C12-C14 aliphatic saturated hydrocarbon. 5. The method for deinking paper according to claim 3, wherein the solvent is an ether. 6. The solvent is diethylene glycol n-butyl ether.
4. A method for removing ink from paper according to claim 3. 7. The method of claim 1 further comprising collecting toner particles. 8. The method for deinking paper according to claim 7, further comprising recycling the toner particles. 9. The method for deinking paper according to claim 1, further comprising collecting vapor generated by heating. 10. The paper of claim 9 wherein collecting the vapor comprises condensing the collected vapor back into a liquid deinking solution and recycling the condensed deinking solution. Method. 11. The method of claim 1, wherein removing comprises wiping the sheet to remove toner particles. 12. The method of claim 11, wherein wiping comprises rotating the coil brush to remove toner particles from the sheet. 13. The method of deinking paper according to claim 12, wherein the wiping further comprises collecting toner particles from a coil brush. 14. The method of claim 13 wherein collecting comprises combing a coil brush to remove toner particles from the brush. 15. The method of claim 14 wherein combing comprises depositing toner particles in a collection compartment. 16. The method of deinking paper according to claim 1, wherein the heating comprises blowing hot air over the sheet to dry the sheet. 17. The method for deinking paper according to claim 16, wherein the hot air has a temperature of 60 to 70 ° C. 18. Rolling comprises feeding the sheet between heated rollers.
A method for deinking paper according to claim 1. 19. The method for deinking paper according to claim 18, wherein the roller has a temperature of 20 to 60 ° C. 20. The ink of claim 1, wherein water comprises 75-87% of the deinking solution.
A method for removing ink from the paper described in 1. 21. The method for deinking paper according to claim 1, wherein the surfactant comprises 1 to 3% of the deinking solution. 22. The method for deinking paper according to claim 1, wherein the solvent comprises 15 to 20% of the deinking solution. 23. The deinking solution has a pH in the range of 6.5 to 7.5.
A method for deinking paper according to claim 1. 24. The method of deinking paper according to claim 1, wherein the solvent comprises a glycol ether and an aromatic hydrocarbon. 25. The glycol ether is selected from the group consisting of ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, ethylene glycol n-butyl acetate, and diethylene glycol n-butyl acetate. A method for removing ink from the paper described in 1. 26. The paper of claim 25, wherein the aromatic hydrocarbon is selected from the group consisting of ethyl 4-methoxybenzoate, ethyl 3-methoxybenzoate, and ethyl 2-methoxybenzoate. How to pull out. 27. A system for deinking a sheet of paper by removing toner thereon, means for wetting the sheet of paper with a non-toxic aqueous de-inking solution; wherein: The solution is water for wetting a sheet of paper and swelling the fibers of the sheet; a water-soluble surfactant for reducing the surface tension of the water and promoting wetting of the sheet with water; Means for softening the toner without dissolving and breaking up the bond between the toner and the sheet, including two or less water-soluble solvents, for removing the softened toner from the sheet to form toner particles Means for heating the sheet to evaporate the deinking solution and remove the solution from the sheet, and means for rolling the sheet of paper and returning the sheet to a predetermined size for immediate reuse. Including It said of the system. 28. The system for deinking paper according to claim 27, wherein the water and the surfactant are in a 10: 1 ratio in the deinking solution. 29. The surfactant is Triton X-155, Triton X-305, Triton X-4.
28. The system for deinking paper according to claim 27, wherein the system is selected from the group consisting of 05 and BRD 2311. 30. The system for deinking paper according to claim 28, wherein the deinking solution further comprises a solvent in a 3:10 ratio to water and surfactant. 31. The system for deinking paper according to claim 30, wherein the solvent is a C12-C14 aliphatic saturated hydrocarbon. 32. The system for deinking paper according to claim 30, wherein the solvent is an ether. 33. The system for deinking paper according to claim 30, wherein the solvent is diethylene glycol n-butyl ether. 34. The apparatus of claim 27, further comprising means for collecting toner particles.
A system for removing ink from paper described in 1. 35. The system for deinking paper according to claim 34, further comprising means for recycling toner particles. 36. The system for deinking paper according to claim 27, further comprising means for collecting steam generated by the heating. 37. The method of claim 36, wherein the means for collecting vapor includes means for condensing the collected vapor back into a liquid deinking solution, and means for recycling the condensed deinking solution. A system for removing ink from paper. 38. The system for deinking paper according to claim 27, wherein the means for removing includes means for wiping the sheet to remove toner particles. 39. The system for deinking paper according to claim 38, wherein the means for wiping includes means for rotating the coil brush to remove toner particles from the sheet. 40. The system for deinking paper according to claim 39, wherein the means for wiping further comprises means for collecting toner particles from a coil brush. 41. The system for deinking paper according to claim 40, wherein the means for collecting toner particles includes means for combing a coil brush to remove toner particles from the brush. 42. The system for deinking paper according to claim 41, wherein the means for combing comprises means for depositing toner particles in the collection compartment. 43. The system for deinking paper according to claim 27, wherein the means for heating includes means for blowing hot air onto the sheet to dry the sheet. 44. The system for deinking paper according to claim 43, wherein the hot air has a temperature of 60-70 ° C. 45. The system for deinking paper according to claim 27, wherein the means for rolling comprises means for feeding the sheet between heated rollers. 46. The system for deinking paper according to claim 45, wherein the rollers have a temperature of 20 to 60 ° C. 47. The ink of claim 2 wherein water comprises 75-87% of the deinking solution.
A system for ink removing paper according to claim 9. 48. The system for deinking paper according to claim 27, wherein the surfactant comprises 1-3% of the deinking solution. 49. The system for deinking paper according to claim 27, wherein the solvent comprises 15-20% of the deinking solution. 50. The deinking solution has a pH in the range of 6.5 to 7.5.
A system for deinking paper according to claim 27. 51. The system for deinking paper according to claim 27, wherein the solvent comprises a glycol ether and an aromatic hydrocarbon. 52. The method of claim 51, wherein the glycol ether is selected from ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, ethylene glycol n-butyl acetate, and diethylene glycol n-butyl acetate. A system for removing ink from the paper described. 53. The paper ink of claim 52, wherein the aromatic hydrocarbon is selected from the group consisting of ethyl 4-methoxybenzoate, ethyl 3-methoxybenzoate, and ethyl 2-methoxybenzoate. System for unplugging.